At the time of examination, chronic neurologic abnormalities had been present from 3 months to 14 years, usually with little progression. Six months after a two-week course of intravenous ceftriaxone (2 g daily), 17 patients (63 percent) had improvement, 6 (22 percent) had improvement but then relapsed, and 4 (15 percent) had no change in their condition.

Later extracutaneous manifestations developed in 27% of the patients with erythema migrans and in 47% of the patients with ACA despite antibiotic therapy. We could not prove the superiority of any antibiotic tested in either early or late European Lyme borreliosis.

The word “chronic” has been applied to Lyme disease in a wide variety of contexts
and is sometimes used interchangeably with the preferred term “late Lyme disease.”
For example, in Europe, certain late neurologic manifestations of previously untreatedor inadequately treated infection, such as borrelial encephalomyelitis or long-standing
meningitis, have been referred to as “chronic neuroborreliosis” (Table 1).1-3

I found this on facebook and I think this is written by av person from France (and this was posted by the US woman that is mentioned in the following thread in this forum: viewtopic.php?f=6&t=6291 ):

Lyme borreliosis is an infectious disease caused by a bacterium and transmitted by a tick bite. The controversy relates to the existence or not of chronic forms (that is to say, whose conventional treatments do not overcome) of this disease. Associations have been demanding for several years the recognition of these chronic forms.

I recommend this person to call this treatment failure, relapse or persistent Lyme borreliosis after treatment instead, since chronic (Lyme) borreliosis is synonymous with late Lyme disease (stage 3) in many countries.